This invention relates to improved controls for animal feeders. As herein illustrated, these controls are embodied in connection with a storage tank serving as a receptacle for a supply of water mounted in elevated spaced relation to an underlying feed tray and functionally related to a supply of dry feed. The arrangement is such that when feeding animals cause the mixture in the tray to fall to a predetermined level, the controls are responsively caused to automatically function to replenish the tray with water and dry feed, in the proper proportions.
The pertinent prior art is best exemplified in U.S. Pat. No. 3,016,044. While the apparatus therein illustrated has worked remarkably well, it has been found that unforeseen external factors can cause a malfunction thereof during extended periods of limited feeding, such as during night hours. This malfunction has been found to occur when the level of the liquid matter in the feed tray falls to a point where it is about to, but does not quite clear the lower end of the extension 15 depending from the overlying tank 10 shown in the U.S. Pat. No. 3,016,044. Under such circumstances, if the apparatus is subjected to vibration, such as may occur, for example, when water is drawn, for unrelated purposes, from the line serving to maintain a supply thereof in the storage tank 10, or when the feeder structure is repeatedly bumped by a feeding animal, there can be a temporary break in the attachment of the water to and about the lower end of the extension 15. This produces a temporary air passage permitting small quantities of air to enter the extension 15 and the pipe 18 illustrated in said patent. This air will pass into and increase the buoyancy of the flotation-type valve member which normally seals the tank discharge opening. Repeated occurrences of this nature can increase the buoyancy of the valve member to such an extent as to place the valve member in an unstable condition, under which circumstances it may be temporarily or partially unseated, to a limited degree, under the influence of further applied vibration. The degree of unseating of the valve is generally minimal and sufficient only to result in leakage of small amounts of water from the storage tank to the underlying tray. However, if unobserved, the leaking water will eventually fill the tray, and without a proportioned addition of the dry feed which is essential to the diet of the feeding animals. It will be understood, of course, that unless the leaking water is accompanied by a prescribed amount of dry feed, the resulting mixture in the feed tray will provide an improper diet for the feeding animals and their health will be impaired.
The aforementioned problem has occurred and can occur only under certain unusual conditions such as above set forth and it can be compensated for on careful watch of the apparatus on the part of the farmer. However, this is not a practical solution to the problem. The proper solution to the problem is one which will relieve the burden and the responsibility for careful attendance on the part of the farmer and this is what has been simply but quite uniquely, effected by the present invention.